--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/pass1.c	Wed Jan 19 22:27:17 2011 -0700
@@ -0,0 +1,316 @@
+/*
+pass1.c
+
+Copyright © 2010 William Astle
+
+This file is part of LWTOOLS.
+
+LWTOOLS is free software: you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+more details.
+
+You should have received a copy of the GNU General Public License along with
+this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <stdio.h>
+#include <string.h>
+
+#include <lw_alloc.h>
+#include <lw_string.h>
+
+#include "lwasm.h"
+#include "instab.h"
+#include "input.h"
+
+extern int expand_macro(asmstate_t *as, line_t *l, char **p, char *opc);
+extern int expand_struct(asmstate_t *as, line_t *l, char **p, char *opc);
+
+/*
+pass 1: parse the lines
+
+line format:
+
+[<symbol>] <opcode> <operand>[ <comment>]
+
+If <symbol> is followed by a :, whitespace may precede the symbol
+
+A line may optionally start with a number which must not be preceded by
+white space and must be followed by a single whitespace character. After
+that whitespace character, the line is parsed as if it had no line number.
+
+*/
+void do_pass1(asmstate_t *as)
+{
+	char *line;
+	line_t *cl;
+	char *p1;
+	int stspace;
+	char *tok, *sym;
+	int opnum;
+	int lc = 1;
+	for (;;)
+	{
+		sym = NULL;
+		line = input_readline(as);
+		if (!line)
+			break;
+		if (line[0] == 1 && line[1] == 1)
+		{
+			// special internal directive
+			// these DO NOT appear in the output anywhere
+			// they are generated by the parser to pass information
+			// forward
+			for (p1 = line + 2; *p1 && !isspace(*p1); p1++)
+				/* do nothing */ ;
+			*p1++ = '\0';
+			if (!strcmp(line + 2, "SETCONTEXT"))
+			{
+				as -> context = strtol(p1, NULL, 10);
+			}
+			lw_free(line);
+			lc = 1;
+			continue;
+		}
+		debug_message(as, 75, "Read line: %s", line);
+		
+		cl = lw_alloc(sizeof(line_t));
+		memset(cl, 0, sizeof(line_t));
+		cl -> outputl = -1;
+		cl -> linespec = lw_strdup(input_curspec(as));
+		cl -> prev = as -> line_tail;
+		cl -> insn = -1;
+		cl -> as = as;
+		cl -> inmod = as -> inmod;
+		cl -> csect = as -> csect;
+		cl -> pragmas = as -> pragmas;
+		cl -> context = as -> context;
+		cl -> ltext = lw_strdup(line);
+		cl -> soff = -1;
+		cl -> dshow = -1;
+		cl -> dsize = 0;
+		cl -> dptr = NULL;
+		cl -> isbrpt = 0;
+		as -> cl = cl;
+		if (!as -> line_tail)
+		{
+			as -> line_head = cl;
+			cl -> addr = lw_expr_build(lw_expr_type_int, 0);
+		}
+		else
+		{
+			lw_expr_t te;
+
+			cl -> lineno = as -> line_tail -> lineno + 1;
+			as -> line_tail -> next = cl;
+
+			// set the line address
+			te = lw_expr_build(lw_expr_type_special, lwasm_expr_linelen, cl -> prev);
+			cl -> addr = lw_expr_build(lw_expr_type_oper, lw_expr_oper_plus, cl -> prev -> addr, te);
+			lw_expr_destroy(te);
+			lwasm_reduce_expr(as, cl -> addr);
+//			lw_expr_simplify(cl -> addr, as);
+
+			// carry DP value forward
+			cl -> dpval = cl -> prev -> dpval;
+			
+		}
+		if (!lc && strcmp(cl -> linespec, cl -> prev -> linespec))
+			lc = 1;
+		if (lc)
+		{
+			cl -> lineno = 1;
+			lc = 0;
+		}
+		as -> line_tail = cl;
+		// blank lines don't count for anything
+		// except a local symbol context break
+		if (!*line)
+		{
+			as -> context = lwasm_next_context(as);
+			goto nextline;
+		}
+	
+		// skip comments
+		// commends do not create a context break
+		if (*line == '*' || *line == ';' || *line == '#')
+			goto nextline;
+
+		p1 = line;
+		if (isdigit(*p1))
+		{
+			// skip line number
+			while (*p1 && isdigit(*p1))
+				p1++;
+			if (!*p1 && !isspace(*p1))
+				p1 = line;
+			else if (*p1 && !isspace(*p1))
+				p1 = line;
+			else if (*p1 && isspace(*p1))
+				p1++;
+		}
+
+		// blank line - context break
+		if (!*p1)
+		{
+			as -> context = lwasm_next_context(as);
+			goto nextline;
+		}
+
+		// comment - no context break
+		if (*p1 == '*' || *p1 == ';' || *p1 == '#')
+			goto nextline;
+
+		if (isspace(*p1))
+		{
+			for (; *p1 && isspace(*p1); p1++)
+				/* do nothing */ ;
+			stspace = 1;
+		}
+		else
+			stspace = 0;
+
+		if (*p1 == '*' || *p1 == ';' || *p1 == '#')
+			goto nextline;
+		if (!*p1)
+		{
+			// nothing but whitespace - context break
+			as -> context = lwasm_next_context(as);
+			goto nextline;
+		}
+
+		// find the end of the first token
+		for (tok = p1; *p1 && !isspace(*p1) && *p1 != ':' && *p1 != '='; p1++)
+			/* do nothing */ ;
+		
+		if (*p1 == ':' || *p1 == '=' || stspace == 0)
+		{
+			// have a symbol here
+			sym = lw_strndup(tok, p1 - tok);
+			if (*p1 == ':')
+				p1++;
+			for (; *p1 && isspace(*p1); p1++)
+				/* do nothing */ ;
+			
+			if (*p1 == '=')
+			{
+				tok = p1++;
+			}
+			else
+			{
+				for (tok = p1; *p1 && !isspace(*p1); p1++)
+					/* do nothing */ ;
+			}
+		}
+		if (sym && strcmp(sym, "!") == 0)
+			cl -> isbrpt = 1;
+		else if (sym)
+			cl -> sym = lw_strdup(sym);
+		cl -> symset = 0;
+		
+		// tok points to the opcode for the line or NUL if none
+		if (*tok)
+		{
+			// look up operation code
+			sym = lw_strndup(tok, p1 - tok);
+			for (; *p1 && isspace(*p1); p1++)
+				/* do nothing */ ;
+
+			for (opnum = 0; instab[opnum].opcode; opnum++)
+			{
+				if (!strcasecmp(instab[opnum].opcode, sym))
+					break;
+			}
+			
+			// p1 points to the start of the operand
+			
+			// if we're inside a macro definition and not at ENDM,
+			// add the line to the macro definition and continue
+			if (as -> inmacro && !(instab[opnum].flags & lwasm_insn_endm))
+			{
+				add_macro_line(as, line);
+				goto linedone;
+			}
+			
+			// if skipping a condition and the operation code doesn't
+			// operate within a condition (not a conditional)
+			// do nothing
+			if (as -> skipcond && !(instab[opnum].flags & lwasm_insn_cond))
+				goto linedone;
+        	
+			if (instab[opnum].opcode == NULL)
+			{
+				cl -> insn = -1;
+				if (*tok != ';' && *tok != '*')
+				{
+					// bad opcode; check for macro here
+					if (expand_macro(as, cl, &p1, sym) != 0)
+					{
+						// macro expansion failed
+						if (expand_struct(as, cl, &p1, sym) != 0)
+						{
+							// structure expansion failed
+							lwasm_register_error(as, cl, "Bad opcode");
+						}
+					}
+				}
+			}
+			else
+			{
+				cl -> insn = opnum;
+				// no parse func means operand doesn't matter
+				if (instab[opnum].parse)
+				{
+					if (as -> instruct == 0 || instab[opnum].flags & lwasm_insn_struct)
+					{
+						cl -> len = -1;
+						// call parse function
+						(instab[opnum].parse)(as, cl, &p1);
+					
+						if (*p1 && !isspace(*p1))
+						{
+							// flag bad operand error
+							lwasm_register_error(as, cl, "Bad operand (%s)", p1);
+						}
+					}
+					else if (as -> instruct == 1)
+					{
+						lwasm_register_error(as, cl, "Bad operand (%s)", p1);
+					}
+				}
+			}
+		}
+	
+	linedone:
+		lw_free(sym);
+		
+		if (!as -> skipcond && !as -> inmacro)
+		{
+			if (cl -> sym && cl -> symset == 0)
+			{
+				debug_message(as, 50, "Register symbol %s: %s", cl -> sym, lw_expr_print(cl -> addr));
+	
+				// register symbol at line address
+				if (!register_symbol(as, cl, cl -> sym, cl -> addr, symbol_flag_none))
+				{
+					// symbol error
+					// lwasm_register_error(as, cl, "Bad symbol '%s'", cl -> sym);
+				}
+			}
+			debug_message(as, 40, "Line address: %s", lw_expr_print(cl -> addr));
+		}
+		
+	nextline:
+		lw_free(line);
+		
+		// if we've hit the "end" bit, finish out
+		if (as -> endseen)
+			return;
+	}
+}